In the field of the duplication of prints, the improvement in the working efficiency of the photomechanical process has been desired in order to meet the variety of and the complexity of printed materials.
In the step of montaging and film-contacting works improvement in the working efficiency has been made by carrying out the work under more light circumstance. For the purpose, the development of a silver halide photographic material for plate making capable of being handled under what could be considered to be a substantially light room and the development of an exposure printer have proceeded.
The silver halide photographic material for a light room as used in the description of the present invention means a silver halide photographic material which can be used under light of wavelengths of at least 400 n.m. not including ultraviolet components as safe-light.
The silver halide photographic material for light room being used for montaging and film-contacting works is a photographic material which is utilized to achieve a negative image/positive image transformation or a positive/negative image transformation. This transformation is achieved by contact exposure of the silver halide photographic material for duplication using a developed photographic film having formed thereon characters or dot images as an original. This original must have;
(1) a performance that a dot image, a line image, and a character image are subjected to negative image/positive image transformation in conformity with the dot area, the line width, and the character image width, respectively and PA1 (2) a performance that the tone of a dot image and the line width of a character image and a line image can be controlled.
Silver halide photographic materials for contact in a light room capable of meeting these requirements have been proposed.
However, a conventional silver halide photographic material for contact in a light room has the disadvantage that in the control of dot images in a duplication step in a light room using the light-sensitive material for a light room, the exposure turns out to be an under exposure and the density of a portion which ought to be wholly developed and blackened tends to be greatly reduced.
It is known that if the silver halide grains are made finer the density can be recovered. However, in the case of using silver halide grains mainly composed of silver chloride, since the solubility of the silver halide grains is high, the grains are formed by reducing the temperature at grain formation or increasing the addition speed of a halide solution and a silver salt solution to reduce the sizes of the silver halide grains formed. However, there is a problem that during the grain formation and after the grain formation, physical ripening proceeds and in particular, the grain sizes become large during desalting.
Also, when silver halide grain formation is carried out at a low temperature of 30.degree. C. or less, it is difficult to control the temperature at a constant value for production convenience. Hence, a method of stably producing the silver halide grains at such a low temperature has been desired.
Furthermore, when fine silver chloride grains are used, there is a problem that uneven processing tends to occur on photographic processing of the silver halide photographic material. In particular, the occurrence of uneven squeezing of the rollers (physical developed stains) in the developing portion of an automatic processor is a serious problem.
Also, in each of a lithographic development, a RAS development which is widely useful and simple controllable development with no specific development advantage, and a hybrid development which uses amine compound as an accelerator and shows super high contrast photographic properties due to development advantage, a silver halide photographic material stably providing a high toe contrast and high Dmax in a stable manner has been desired.